Before surgical staplers were introduced, surgeons had to spend a great deal of time sewing the tissue of patients back together. This was the most time intensive aspect of a surgical procedure. Surgical staplers have decreased the amount of time that a user spends sewing tissue back together. Such surgical staplers are described in the following issued U.S. patents which are hereby incorporated herein by reference: U.S. Pat. No. 4,633,861 Chow et al.; U.S. Pat. No. 4,633,874 Chow et al.; and U.S. Pat. No. 5,129,570 Schulze et al.
One concern with surgical staplers has been assuring that the staplers used during a procedure are sterile. Reusable staplers have typically been relatively complicated mechanical instruments which are difficult to sterilize after use. Hence, it was once desired that surgical staplers be completely disposable. As more than one surgical stapler may be required in a surgical procedure, for economical reasons disposable surgical staplers having reloadable staple cartridges have been developed. These reloadable staple cartridges have comprised a combination of staples and a firing module for discharging the staples. Typically the cutting instrument is included in the firing module. Therefore, each time a stapler is reloaded with a new staple cartridge, a new knife and firing assembly is also inserted into the stapler. Numerous staple cartridges are normally used during a single patient procedure, resulting in the repeated replacement of the knife and firing elements for the same patient. Since a knife is usually not worn out after a staple cartridge has been emptied, the knife and firing assembly could be reused with additional staple cartridges within the same patient. Reusing the firing assembly within a single patient procedure would not require additional sterilizing and can decrease the costs incurred during the procedure. Recently, there has also been a desire to make portions of a surgical stapler reusable, so that a portion is disposable and a portion is reusable in subsequent procedures. Reusing portions of the stapler reduces the costs associated with surgical procedures, and also decreases the surgical waste.
Thus, to reduce the costs associated with surgical procedures, there is a need for a surgical stapler that can be disassembled and portions of the stapler reconditioned for subsequent use. In particular, there is a need for a surgical stapler in which the firing and cutting components may be reused with multiple staple cartridges within a single patient procedure in order to decrease the amount of materials utilized with the stapler. There is also a need for a surgical stapler that can be easily assembled and disassembled to allow reconditioning and reuse of some of the stapler parts. In addition, there is a need for a partially reusable stapler that incorporates a disposable firing module to allow the more complex cutting and stapling components to be easily replaced between surgical procedures. Further, there is a need for a partially reusable stapler in which the reusable parts have a simple, one-piece design to facilitate effective reconditioning of the parts between procedures. The present invention provides a partially reusable surgical stapler which achieves these objectives.